This paper proposes a short and subjective review of the development and use of Multi-Agent Systems (MAS) for ecosystem management. The use of these tools go with the shifts in various paradigms on the study of ecological complexity, the introduction of behavior and interactions as the key issues to understand the organization, and the use of models in a constructivist way. Multi-Agent Systems are introduced in a conceptual way and some computer tools are presented. Then a discussion is proposed on the use of MAS for problems integrating social and spatial aspects. MAS may be used for several purposes from theorization to collective decision-making support.